1. Field of the Invention
The invention relates to web services. Specifically, the invention relates to apparatus, systems, and methods for defining a web services interface for MFS-based IMS applications.
2. Description of the Related Art
Computer and information technology continues to progress and provide tools that allow software applications to interact more easily than in the past. For example, web services have been introduced recently as a standard interface allowing one software application to utilize a feature or function of another software application over a public network without obstacles such as proprietary message formats, encoding, firewall access, and the like.
To control costs, web services need to interface with other computer and information technology which remain largely unchanged. For example, large corporations, governments, and other entities continue to use legacy applications, software programs designed, written, and maintained for large, mission-critical computers, such as mainframes. These entities have invested large amounts of work and money into developing and maintaining the legacy applications. In addition, these applications have been tested and refined to operate very efficiently and with minimal errors.
Legacy applications continue to manage a high percentage of the everyday transactions and data for these businesses. One example of legacy applications in wide-spread use are Message Format Service-based Information Management System applications (hereinafter MFS-based IMS applications). MFS is a component of the transaction management module for IMS. MFS translates transaction messages between various devices and the MFS-based IMS application.
Converting or upgrading MFS-based IMS applications to the latest technologies and standards, such as web services, is often costly and/or impractical. Instead, components are built to translate messages between software applications executing modern standards and technologies and the MFS-based IMS applications.
For example, XML-MFS adapters have been built which convert between web services messages utilizing eXtended Markup Language (XML) and Simple Object Access Protocol (SOAP) and proprietary transaction messages used by MFS-based IMS applications. In this manner, MFS-based IMS applications benefit from the new standards and technologies without making any changes to the MFS-based IMS applications themselves.
Proprietary transaction messages used by MFS-based IMS applications insulate the MFS-based IMS application from the differences in characteristics and layout among different device types and device features that cooperate to provide an interface for the MFS-based IMS application. The devices interfacing with MFS-based IMS applications may include hardware and software including different terminals, keyboards, mouse devices, monitors, light pens, touch screens, card readers, and the like. Instead of device specific code in each MFS-based IMS application, a common MFS control block known as a Message Input Description (MID) and Message Output Description (MOD) is defined for the different device types.
The MID and MOD define how the input or output messages are formatted and laid out for the specific input/output device. MFS supports a plurality of devices including the IBM 3270 terminal. MFS uses the MIDs/MODs to manage interface information such as field formats, field layouts, input devices, and the like. Because MFS manages the interface specific information, the MFS-based IMS application may focus on business logic that utilizes the inputs and outputs.
As mentioned above, XML-MFS adapters allow non-MFS based IMS applications to interface with MFS-based IMS applications for implementing e-commerce software such as web services. Non-MFS based IMS applications send XML messages to the XML-MFS adapter, which provides messages in the MID/MOD format to the MFS-based IMS application. However, MFS-based IMS applications typically support a large number of devices, which means that a corresponding large number of MIDs/MODs are defined. The XML-MFS adapter needs to know which MID and associated Device Input Formats (DIFs) and which MODs and associated Device Output Formats (DOFs) define an application interface for the MFS-based IMS application providing the web service.
This MFS-based IMS application interface may be defined in an XMI (XML Metadata Interchange) file. The XML-MFS adapter uses the XMI files to convert an XML message from a non-MFS based IMS application, such as a servlet, Java bean, or SOAP client application, into the appropriate MFS input and output messages to communicate with the MFS-based IMS application.
Using XMI files, the XML-MFS adapter performs the run-time conversion of XML messages into suitable MID/DIF and MOD/DOF messages and vice versa. In addition, a code generation tool may use XMI files to build a servlet implementing a web service on a web server. Furthermore, a web services description tool uses the XMI files to produce a description of the web service suitable for a web services directory such as a Uniform Description, Discovery, Integration (UDDI) directory. The web services description tool formats the web services description into a Web Services Description Language (WSDL) file.
Unfortunately, no user tools exist for building suitable XMI files to define the web services application interface for an MFS-based IMS application. XMI files may be written manually using a text editor, though such a process is time consuming, error prone, and requires the author to have intimate knowledge regarding the MID and associated MODs supported by the MFS-based IMS application that the XMI files are intended to represent. Furthermore, the author must know which required MODs to include in the XMI files. In addition, the author must now how a desired MID for implementing the web service is associated with one or more MODs.
Accordingly, what is needed is an apparatus, system, and method for defining a web services interface for an MFS-based IMS application. In particular, the apparatus, system, and method should automate the generation of XMI files that define a web services interface for an MFS-based IMS application that includes a user-selected MID, one or more associated MODs, and any required MODs. To be most beneficial the apparatus, system, and method should also allow a MID/MOD selection for preexisting XMI files to be readily revised.